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Copper-matrix composites reinforced with SiC particles are prepared by mechanical alloying. The microstructure characteristics, relative density, hardness, tensile strength, electrical conductivity, thermal conductivity and wear properties of the composites are investigated in this paper. The results indicate that the relative density, macro-hardness and mechanical properties of composites are improved by modifying the surface of SiC particles with Cu and Ni. The electrical conductivity and thermal conductivity of composites, however, are not obviously improved. For a given volume fraction of SiC, the Cu/SiC_(Ni) has higher mechanical properties than Cu/SiC_(Cu). The wear resistance of the composites are improved by the addition of SiC. The composites with optimized interface have lower wear rate.

Iron-based composite coatings reinforced with TiB₂–TiC multiple ceramic have been fabricated from a precursor of B₄C, TiO₂ and Al powders by laser cladding. The effect of TiO₂ and Al on the microstructure and wear properties of the coatings was investigated. The results showed that the volume fraction, type and size of the reinforcements were influenced by the content of TiO₂ and Al. TiB₂ and TiC were evenly distributed in the coating; however, most of Al₂O₃ were ejected from the coatings, only few of them retained in the coating acting as nucleation core of reinforcement or inclusion. The microhardness and wear resistance of the coatings were improved, whereas the friction coefficients of the coatings were considerably lower than that of substrate.

The study focuses on the influence of SiC and heat treatment effect on mechanical and wear behavior of Aluminium Metal Matrix Composites (AMMCs), Al7075 is the matrix material and composites were prepared by varying the weight percentage of SiC. The prepared composites are divided into two groups Type A and Q samples while Type Q was artificially aged to T6 condition. In addition to the reinforcement, the hard intermetallic secondary phase that emerges due to heat treatment strengthens the AMMCs with a considerable degree of embrittlement. Both Type A and Q samples were characterized for various mechanical properties such as hardness, tensile strength, impact strength, etc. A new regression mathematical model was developed to predict the mechanical properties. Wear testing was done by varying load for a fixed distance and observed a good percentage of improvement in hardness, tensile strength, impact strength, and specific wear rate for 9% reinforced SiC AMMCs relative base alloy.

In this study, coal ash/recycled plastic composite material was fabricated with post-consumer high-density polyethylene (HDPE) and coal ash particles. The main idea of using coal ash, since it is also a waste product, as reinforcing filler in recycled HDPE is to reduce the cost, develop lightweight and produce environmental-friendly materials. Coal ash/recycled plastic composite have been used in significant applications as construction materials including flooring, landscaping, fencing, railing window framing and roof tiles. Effect of coal ash loading on the mechanical properties and thermal conductivity of coal ash/recycled HDPE composite were determined. It is expected to use waste materials in new field by getting novel composite materials with developed mechanical properties. It was found that coal ash filler indicated significant improvement on the mechanical properties of composites. The results show that the impact decreased tremendously from 57.32 to 15.8kJ/m² with only 30wt.% loading of coal ash. The filler increases the elasticity of the material and reduces its ability to absorb deformation energy.